If it were me and it was driving me nuts I would do some stitching on the cat - stitch where the tail and body meet then go and stitch the lines of the cat legs up on to the body - to accentuate the different parts of the body - kind of like making a coloring page outline so instead of a silhouette you would have the details stitched in. It will look more like you meant to do it and tie it all together. Stitch the outlines in of the eyes and whiskers too possibly and the ears... but do it all in black not in a noticeable color. The added stitching will make the tail piece seam not as noticeable.